Insulation For The Walls Of The House Outside For Siding: Options For The Facade Of A Wooden House, Polystyrene And Polystyrene Foam For Outdoor Use

2024 Author: Beatrice Philips | [email protected]. Last modified: 2024-01-09 13:15

Siding is very widely used for finishing a wide variety of residential buildings - both private and multi-apartment buildings. But the Russian climate forces us to constantly take care of the maximum heat saving. And therefore, the choice of high-quality insulation is of great importance. Moreover, it should be not only of high quality, but also fully consistent with the characteristics of a particular dwelling.

Why is this needed?

Heating buildings in winter requires huge expenses and significantly affects the financial situation of residents. Only high-class insulation helps to reduce costs and ensure a high level of comfort at the same time. On their own, wood and thick brick walls will not retain heat, and when siding is still placed outside, it can increase the risk of cooling the home. It is imperative to take care of thermal insulation and the creation of a heat-retaining gap between the main wall and the decorative surface. These requirements fully apply to frame houses.

Types: pros and cons

In any hardware store and on the market, consumers are offered a variety of materials and technological solutions that are presented as universal products. But in reality this does not happen: a certain type of insulation has a strictly limited application, and only within a strictly defined framework does it reveal its capabilities.

Among inexpensive and technologically simple solutions, one of the leading positions is invariably occupied by foam. It is lightweight and can be attached to the base of the wall using dowels or special glue. The lightness of the material does not prevent it from having high rigidity and relative strength. Even in contact with water, the insulation will reliably perform its function, no matter how strong the frost is on the street.

The foam also has objective disadvantages:

• the maximum service life of the material is only 15 years;
• vapor permeability is insufficient;
• the need for additional ventilation.

To insulate the facade walls, not just any foam is useful, but only processed by the extrusion method (officially called polystyrene foam). Such insulation is not subject to shrinkage, but requires increased sound insulation, as it sometimes amplifies external noise.

Mineral wool is recommended for both metal and plastic siding , professionals consider slabs 1000x50 mm in size to be its best variety. The rolls gradually shrink, and there is a high risk of losing the insulation in the upper part of the wall after a short time. The disadvantages of such a coating are the significant need for vapor barrier, the need to cover the material from moisture from the outside. If you are going to install mineral wool, you need to take measures to protect against fine dust particles. The rest of the basalt insulation performs relatively well.

Often in the catalogs of construction companies you can find the so-called penoplex. There is nothing unusual about it, since it is all the same expanded polystyrene that was extruded at elevated pressure (such a technological process creates a structure of small cells). At factories, penoplex is produced in the form of plates with a thickness of 2 to 10 cm.

The advantage of the material is the uniform distribution of air bubbles throughout the mass. Due to this property, it transmits heat very little and is little susceptible to the effects of water. In the course of tests, a number of thermal technical examinations confirmed that when the penoplex is drowned in 30 days, it becomes heavier by only 0.06%, that is, water can only penetrate into the cut ends of the products.

Of the minuses, it can be noted that this insulation is easily destroyed under the action of:

• acetone;
• formaldehyde;
• paint thinners;
• gasoline, kerosene, diesel fuel;
• oil paint and a number of other organic substances.

The complexity of the technology leads to the fact that penoplex is more expensive than almost any mass insulation, excluding mineral wool. After installation, cover the surface of the material as soon as possible before it is destroyed by direct sunlight. Like all derivatives of polystyrene, even foil-clad penoplex does not allow you to protect yourself from the appearance of a house mouse in the walls. We'll have to take additional measures to combat this rodent. A serious problem is also the easy ignition of this kind of insulation, which negates even its acceptable density.

How to choose?

For walls finished with any type of siding, you need to choose insulation, focusing on the following criteria:

• thermal conductivity level;
• the intensity of moisture absorption (liquid and from the air);
• its protection from the action of fire;
• the required layer thickness.

Thermal conductivity (how much heat is retained) is a key parameter that characterizes a material as insulating. But even between their individual species, it varies quite widely. So, heat is escaping the most through mineral wool, and the least leakage will be through foam. Confusion is in vain: recommendations to choose cotton wool are made taking into account other valuable properties of the material.

Insulation materials inevitably meet with moisture deposited from air streams, if the integrity of the "pie" is broken, droplets (trickles) of liquid water can also penetrate. Therefore, when choosing the final version, they are always guided by how much water the substance will absorb without losing its useful characteristics. The easiest way is with the density of the material: the more significant it is, the better it is to use just this type of insulation. But we also have to reckon with the complication of mounting heavier structures.

Fire safety is assessed by how high the flammability of a substance is . And the thickness of the layer being created is a contradictory value. There is no doubt that with its increase, the thermal protection increases noticeably. But a balanced approach is needed, taking into account how dense the material used is. If it is very dense, it is advisable to use a less thick layer.

Some manufacturers are trying to convince consumers that their materials are completely environmentally friendly, made of linen fibers or pure cellulose, and even the glue is selected as natural as possible. Believe such promises or not, everyone must decide on their own, but it is better to think about why professional builders are trying to insulate facades with more familiar products, without overpaying "for the environment." The only exception is glass wool, it is really dangerous to health at the slightest violation of technology or insufficient protection measures.

For outdoor use under siding, it is difficult to find better options than the already mentioned mineral wool and expanded polystyrene. But in order for the result to meet the expectations of the builders, and even the most severe frost does not affect the outside, it is necessary not only to choose the right insulation, but also to apply it according to the recommendations of professionals.

Installation technology

The first step, according to generally accepted technology, is the calculation of the required thermal protection layer. In the Moscow region, houses for siding can be insulated with mineral (or glass) wool, the thickness of which is 50 - 100 mm, in especially difficult conditions this figure can be doubled by making a two-layer structure. It is best not to rely on your own engineering knowledge, online calculators or advice from familiar builders, but request a calculation from the same company that will install the siding.

When the need for the exact amount of material is determined, it is time to prepare the surface.

It runs as follows:

• all lamps and decorative details are removed;
• gutters are disassembled;
• trims on windows and doors are removed (if they have already been installed);

• the rough surfaces of the walls are freed from decaying areas;
• the entire surface of the wood is impregnated with fire retardants;
• if the walls are not wooden, but brick or made of artificial stone, it is necessary to remove the influx and pollution;
• then the concrete or brick is covered twice with a deep-penetrating primer.

Almost all types of siding are installed horizontally , and therefore the crate should go vertically. The distances between its nodes depend on what kind of cladding will be applied, and on the width of the blocks of the selected insulation. Most often, a gap of 0.6 m is provided, but under the layers of mineral wool and glass wool, the bars are mounted with an outer step of 590 mm, then the coating will fit tightly and will not leave anywhere. But the distance from one point of attachment of the bar to another at the bottom cannot be more than 0.5 m.

To keep these parts on a wooden wall, self-tapping screws are used to screw them into the wood, specialized dowels are applied over the brick. Each block is selected so that it is equal in thickness to the insulation (we are talking about installation directly on the wall surface). But when a frame is applied, they take either parts for the lathing with a size of 5x5 cm, or special suspensions in the shape of the letter P.

It is not necessary to mount the siding close to the insulating material, leaving a gap of 40-50 mm, the builders provide reliable ventilation. But this solution requires the installation of an additional crate, the creation of which is taken into account when calculating the amount of materials. When slabs, rolls exceed 100 mm in thickness, it is advisable to give preference to a cross crate (it will allow placing the layers of thermal protection at right angles to each other).

Above mineral wool, glass wool and foam, it is always necessary to place a special membrane that protects simultaneously from moisture and wind from the outside. When studying reviews of such membranes, it is worth paying attention to whether they are good at letting steam out. If this figure is not enough, serious problems may arise.

Cloths for protection from wind and water necessarily overlap each other by at least 0.1 m. When calculating the need for any components, you can safely add another 10% to the resulting figure. Then neither defective products nor installation errors will slow down the construction or repair.

Many novice builders and home craftsmen are attracted by the ease of creating a crate made of wood, which is manifested in the fact that:

• Installation can be done by hand without unnecessary tools.
• The process is not expensive.
• Wooden battens alone minimize heat leakage (compared to steel counterparts).
• The structure can be fixed directly to the wall without adding brackets or other connections.

But positive characteristics cannot exist without disadvantages. Thus, the low cost of the material becomes a less convincing advantage when considering the need for treatment with fire retardants and agents that suppress the growth of microscopic fungi. It turns out to be not such a simple task to select the bars of exactly the required length, which should be even externally and, in addition, dried up to 10 - 12%.

Recommendations

When the insulation is selected and purchased, and the work itself begins, nothing should interfere with the installers. Therefore, although modern technology allows you to operate in any season, it is advisable to choose a dry and warm enough day. Before laying the insulation, it is required to remove everything that can become a hindrance - even the branches of bushes, which can be caught on.

Ecowool in its practical characteristics is identical to the mineral analogue , so the only argument in its favor is increased safety. These two materials are excellent at dampening street noise due to their fibrous, loose thickness. Ecowool will have to be fixed using special devices, and panels are not formed from it. So almost always the installation of this insulation is trusted by professionals. If it is not possible to pay for their services, you will have to consider other methods of thermal protection.

It is advisable to insulate siding placed on wooden walls using materials with the lowest thermal conductivity. We are talking about glass wool and extruded polystyrene foam. The main problem of stone, concrete and brick surfaces is the high level of passing steam, and only hydrophobic materials can effectively resist it. For places where maximum fire protection is required, mineral wool is definitely in the first place.

Instead of a membrane to protect against wind and moisture from outside, some craftsmen use reinforcing layers (made of metal mesh and mortar). There are times when mineral wool is placed in the form of a so-called enclosing form, when mats are placed between two sheets of metal. Such a step helps to guarantee the highest stability of thermal protection, but forces instead to think over the attachment of the cladding to the outer sheet. By placing an insulating material using extreme strips, it is possible to set the location of parts of the decorative material in relation to the insulating layer most accurately.

Sometimes users do not know if it is possible not to insulate the siding at all and not pay for additional materials and work . The answer will be consistently negative, even when the home is in a hot area. After all, high-quality thermal insulation helps not only to keep the heat inside, but also guarantees a rational state of the area between the wall and the finishing panels. If condensation accumulates there, then even the strongest and highest quality material will quickly become unusable. Therefore, responsible owners always carefully consider how to provide thermal insulation under the siding layer in accordance with all technological rules.